TY - JOUR T1 - Magneto-acoustic protein nanostructures for non-invasive imaging of tissue mechanics <em>in vivo</em> JF - bioRxiv DO - 10.1101/2022.05.26.493158 SP - 2022.05.26.493158 AU - Whee-Soo Kim AU - Sungjin Min AU - Su Kyeom Kim AU - Sunghwi Kang AU - Hunter Davis AU - Avinoam Bar-Zion AU - Dina Malounda AU - Yu Heun Kim AU - Soohwan An AU - Jae-Hyun Lee AU - Soo Han Bae AU - Jin Gu Lee AU - Minsuk Kwak AU - Seung-Woo Cho AU - Mikhail G. Shapiro AU - Jinwoo Cheon Y1 - 2022/01/01 UR - http://biorxiv.org/content/early/2022/05/27/2022.05.26.493158.abstract N2 - Measuring cellular and tissue mechanics inside intact living organisms is essential for interrogating the roles of force in physiological and disease processes, and is a major goal in the field of mechanobiology. However, existing biosensors for 3D tissue mechanics, primarily based on fluorescent emissions and deformable materials, are limited for in vivo measurement due to the limited light penetration and poor material stability inside intact, living organisms. While magneto-motive ultrasound (MMUS), which uses superparamagnetic nanoparticles as imaging contrast agents, has emerged as a promising modality for real-time in vivo imaging of tissue mechanics, it has poor sensitivity and spatiotemporal resolution. To overcome these limitations, we introduce magneto-gas vesicles (MGVs), a unique class of protein nanostructures based on gas vesicles and magnetic nanoparticles that produces differential ultrasound signals in response to varying mechanical properties of surrounding tissues. These hybrid protein nanostructures significantly improve signal strength and detection sensitivity. Furthermore, MGVs enable non-invasive, long-term, and quantitative measurement of mechanical properties within 3D tissues and organs in vivo. We demonstrated the performance of MGV-based mechano-sensors in vitro, in fibrosis models of organoids, and in vivo in mouse liver fibrosis models.Competing Interest StatementThe authors have declared no competing interest. ER -